Lab
Sand Springs
Printer Friendly Version
This lab was designed in 1995 for "A Day in the Life of a Student in the 21st Century" - a teleconference with the US House committees on science, economics, and educational opportunities.
Purpose
The purpose of this lab is to produce an oscillation that has a varying amplitude and period. As the sand leaks from the funnel, the period of the spring's oscillation changes
since the mass is constantly decreasing. Moreover, the spring's amplitude also changes as more and more sand leaves the funnel.
A typical graph of this type of oscillation would look like the following sample.
Procedure (set-up)
Under the Start Menu go to Programs, Math, Logger Pro 3.1 to launch the program. Logger Pro should automatically set up the graphs according to the connected sensor. With the Motion Detector properly connected, the program should display graphs of position vs time and velocity vs time. Press Collect to test your connections. Make sure that you are collecting data to at least 3 decimal places.
A second member should verify that the probe is looking at the blue cardboard attached to the top of the funnel - only slight adjustments should be necessary! He/she should then fill the funnel with sand, keeping a finger over the exit hole so that the sand does not immediately run back out, and use the counterweights (slotted masses) to level the cardboard. The purpose of the box is to catch the sand as it leaves the funnel, so please make sure that it is in place before beginning the experiment. Verify that the probe is seeing the cardboard by moving the filled funnel carefully up and down -- DO NOT USE LARGE AMPLITUDES! 5-6 cm is MORE THAN ENOUGH! When everything is working, your are ready to start collecting data.
Procedure (data collection)
Since the sand leaves quickly, the probe should be started first. Try to release your spring with a small steady amplitude and a minimal amount of rotation (twisting). Watch your graphs. The oscillations should minimally have either a constant set of smooth crests OR smooth troughs -- it is not absolutely necessary to have perfect oscillations in both places.
With the completion of each trial, highlight a "good section" of your position vs time graph. The data selected will be highlighted in the accompanying data table. Copy and paste your data into an EXCEL spreadsheet. Rename the sheet Data I.
Carefully refill the funnel to the same level as in your first trial and obtain a second trial. Save this data on a second sheet in the same spreadsheet as Data II.
Finally, refill your funnel to the same level one last time. Record the height of the cardboard. Then record how much time it takes for all of the sand to flow out as it oscillates. Finally, record the final height of the carboard after the funnel is empty and has stopped vibrating.
Run your trials as accurately AND quickly as possible, remember that at least one other group needs to use your lab station before the period is over. When you are finished with both trials, leave the spring & funnel suspended and the sand in the box. Please sweep up and return any sand which got scattered onto the table back to the box. Clear your data from Logger Pro so that the next group can begin.
Analysis
Using your best spreadsheet data from either Trial I or Trial II, record the times and locations of 6 consecutive crests and troughs. Calculate the intermediate equilibrium positions, and then state the amplitude of each crest and trough.
crest/trough
time
position
equilibrium
amplitude
#1
#2
#3
#4
#5
#6
Did the amplitude of the sand spring's oscillations steadily decrease? Support your choice numerically.
calibration
loaded height
empty height
mass of sand
total time
spring constant
Using your time data from Chart #1, fill out the following chart regarding periods and average mass.
interval
period
mass
1-2
2-3
3-4
4-5
5-6
Did the period of the sand spring's oscillations steadily decrease? Support your choice numerically.
Based on the period data calculated in the table above, was the average amount of mass decreasing steadily? Support your choice numerically.
Using your data from emptying the sand spring, at what rate were you expecting the mass to change each second?
Calculate the percent difference between these two rates of mass change.
State a source of error that might justify the percent difference you calculated in the previous question.
Related Documents
Lab:
Labs -
A Physical Pendulum, The Parallel Axis Theorem and A Bit of Calculus
Labs -
Calculation of "g" Using Two Types of Pendulums
Labs -
Conical Pendulums
Labs -
Conical Pendulums
Labs -
Conservation of Energy and Vertical Circles
Labs -
Introductory Simple Pendulums
Labs -
Kepler's 1st and 2nd Laws
Labs -
Loop-the-Loop
Labs -
Moment of Inertia of a Bicycle Wheel
Labs -
Oscillating Springs
Labs -
Roller Coaster, Projectile Motion, and Energy
Labs -
Simple Pendulums: Class Data
Labs -
Simple Pendulums: LabPro Data
Labs -
Video LAB: A Gravitron
Labs -
Video LAB: Circular Motion
Labs -
Video LAB: Looping Rollercoaster
Labs -
Water Springs
Resource Lesson:
RL -
A Derivation of the Formulas for Centripetal Acceleration
RL -
Centripetal Acceleration and Angular Motion
RL -
Conservation of Energy and Springs
RL -
Derivation of Bohr's Model for the Hydrogen Spectrum
RL -
Derivation: Period of a Simple Pendulum
RL -
Energy Conservation in Simple Pendulums
RL -
Gravitational Energy Wells
RL -
Kepler's Laws
RL -
LC Circuit
RL -
Magnetic Forces on Particles (Part II)
RL -
Period of a Pendulum
RL -
Rotational Kinematics
RL -
SHM Equations
RL -
Simple Harmonic Motion
RL -
Springs and Blocks
RL -
Symmetries in Physics
RL -
Tension Cases: Four Special Situations
RL -
The Law of Universal Gravitation
RL -
Thin Rods: Moment of Inertia
RL -
Uniform Circular Motion: Centripetal Forces
RL -
Universal Gravitation and Satellites
RL -
Vertical Circles and Non-Uniform Circular Motion
Review:
REV -
Review: Circular Motion and Universal Gravitation
Worksheet:
APP -
Big Al
APP -
Ring Around the Collar
APP -
The Satellite
APP -
The Spring Phling
APP -
Timex
CP -
Centripetal Acceleration
CP -
Centripetal Force
CP -
Satellites: Circular and Elliptical
NT -
Circular Orbits
NT -
Pendulum
NT -
Rotating Disk
NT -
Spiral Tube
WS -
Basic Practice with Springs
WS -
Inertial Mass Lab Review Questions
WS -
Introduction to Springs
WS -
Kepler's Laws: Worksheet #1
WS -
Kepler's Laws: Worksheet #2
WS -
More Practice with SHM Equations
WS -
Pendulum Lab Review
WS -
Pendulum Lab Review
WS -
Practice: SHM Equations
WS -
Practice: Uniform Circular Motion
WS -
Practice: Vertical Circular Motion
WS -
SHM Properties
WS -
Static Springs: The Basics
WS -
Universal Gravitation and Satellites
WS -
Vertical Circular Motion #1
TB -
Centripetal Acceleration
TB -
Centripetal Force
PhysicsLAB
Copyright © 1997-2019
Catharine H. Colwell
All rights reserved.
Application Programmer
Mark Acton